Irrigation system and fluid dispersion nozzle

ABSTRACT

An agricultural irrigation system having a fluid dispersion nozzle for controlling the flow rate and generating a resultant fluid stream characterized by uniform dispersal along the stream path. The nozzle has a housing member (10) which defines an inlet passageway (16), a nozzle outlet orifice (32), and an intermediate fluid chamber (30). A resilient flow control member (34) is located within the fluid chamber (30) and has an orifice (36) centrally located therein and axially aligned with the inlet passage (16) and the nozzle orifice (32). The nozzle orifice has located along the inner periphery thereof a plurality of circumferentially equally spaced and radially inwardly projecting deflector members (38, 40, 42) which are effective for reducing a portion of the resultant fluid stream velocity therethrough. The fluid dispersion nozzle is mounted on a rotary sprinkler head (50) which receives a supply of pressurized irrigation fluid from an irrigation system primary conduit (56). The sprinkler head is rotated by a water turbine (52) responsive to fluid flow therethrough.

This application is a Continuation-In-Part of my copending application,Ser. No. 879,556, filed Feb. 21, 1978 now abandoned.

FIELD OF THE INVENTION

Agricultural sprinkler systems are presently used in areas where naturalrainfall is insufficient to maintain crop growth. In those areas wherewater supplies are limited, it has become imperative that irrigationtechniques be as efficient as possible in order to conserve water usage.

DESCRIPTION OF THE PRIOR ART

Among the sprinkling techniques presently in use are those using adevice having a rotating nozzle which intermittently discharges a streamof water onto the crop area. An inertial mechanism attached to thesprinkler nozzle utilizes the inertial forces of the water stream torotate the nozzle and hence the water stream throughout 360° of angulardisplacement. A problem encountered with present sprinkler nozzles hasbeen that the high velocity water jet needed for sufficient stream rangeresulted in the area nearest the sprinkler receiving a limited amount ofwater with most of the water falling onto a ring or doughnut-shaped areaof greater radius. Other types of sprinkler nozzles utilize a deflectorarm which intermittently disrupts the water stream permitting the areanear the sprinkler nozzle to receive a greater share of water. However,this type of sprinkler nozzle also lacks a substantially uniform waterapplication pattern. A second separate nozzle is also commonly used inconjunction with a primary nozzle to direct water to the center of thespray pattern.

SUMMARY OF THE INVENTION

In the present invention a substantially uniform water distributionpattern is achieved without the need for additional structural elementsexternal to the sprinkler nozzle for breaking up the flow stream. In thepresent invention a plurality of radially inwardly projecting lugslocated on the outer periphery of the sprinkler nozzle orifice serve todeflect a portion of the water stream, thus permitting a significantamount of water to be uniformly dispersed along the entire length of thewater stream. A further feature of the invention includes theutilization of a resilient flow control element which limits the flowrate through the sprinkler nozzle to a predetermined magnitude andcontrols the diameter of the resultant flow stream within apredetermined range. The flow control element permits the deflectinglugs to uniformly disperse fluid flow over a range of varying supplypressures.

The present invention is also embodied as a sprinkler irrigation systemwhich incorporates the features of the fluid dispersion nozzle asdescribed above. A unique feature of the presently described inventionirrigation system is that the impulse arm, which is ordinarily connectedto the sprinkler head of most prior art sprinkler systems, is eliminatedas uniform water dispersion is more effectively achieved by thedeflector members spaced circumferentially around the outlet orifice ofthe fluid dispersion nozzle. The impulse arm and its associated hardwareare replaced by a far simpler water turbine drive mounted directlywithin the sprinkler head member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a downstream-end view of the device of the present invention;

FIG. 2 is a cross-sectional view taken along section indicating lines2--2 of FIG. 1 showing the invention with the control member undeflectedby any forces accompanying fluid flow;

FIG. 3 is a view similar to FIG. 2 showing the control member in adeflected state under the forces accompanying fluid flow;

FIG. 4 is a chart showing in tabular form the relationship between flowrate, lug size, and flow control member orifice size;

FIG. 5 is a partial cross-sectional view in elevation of a sprinklerhead incorporating the dispersion nozzle of FIGS. 1 through 3; and

FIG. 6 is a schematic view in elevation of a portion of an irrigationsystem incorporating fluid dispersion nozzle of FIGS. 1 and 3.

DETAILED DESCRIPTION OF THE DRAWINGS

In referring to the drawings, like reference numerals designate likeparts in the figures.

Referring now to FIG. 2, a flow dispersion nozzle is indicated generallyby reference numeral 10. An inlet housing section 12 is fluidly sealedand joined to an outlet housing section 14 by any convenient expedient,for example, bonding, a threaded connection, or ultrasonic welding wherethe housing sections are molded from a thermoplastic material. Inservice it has been found desirable to have the junction of the inlethousing to the outlet housing leak-free at 100 p.s.i. static waterpressure of 80 p.s.i. air pressure. An inlet passageway 16 is centrallylocated and formed in inlet housing section 12. A stem portion 18 ofinlet section 12 includes a taper threaded end 20 which permitsattachment to a corresponding internal thread located in a pressurizedwater supply conduit, not shown. A resilient sealing washer 22 is fittedover the stem portion 18 and serves to fluidly seal the dispersionnozzle upon connection to a pressurized water supply conduit. Adownstream surface 24 traverse to inlet passageway 16 is defined byhousing section 12. A second transverse surface 26 and an internaldiameter 28 are defined by outlet housing section 14 and, together withfirst transverse surface 24, define a control chamber 30. As best shownin FIG. 3, an exit orifice 32 is formed in the downstream face of outlethousing section 14 and, in the preferred practice of the invention, iscircular in shape. A resilient, disk-shaped flow control member 34 islocated within control chamber 30. A centrally located control orifice36 is formed in the flow control member and has an internal diametersized less than the internal diameter of inlet passageway 16. Resilientflow control devices of the type described above are known in the artand rely for their means of control upon a restrictive orifice containedtherein which changes size in response to varying fluid pressuredifferentials thereacross. Thus it is essential that the internal areaof any flow passageway immediately upstream from the control orifice besized substantially greater than the area or internal diameter of theflow control member so that the flow control action occurs solely acrossthe flow control member and not in any upstream fluid passageway.

In the preferred practice of the invention, exit orifice 32 is sized tohave an effective area about 20% greater than the area of controlorifice 36 as measured while the flow control member 34 is in a relaxedcondition. This feature enables the fluid stream exiting from thecontrol member 34 to pass through exit orifice 32 while substantiallyavoiding contacting the periphery thereof.

As shown in FIGS. 1 and 2, a series of lugs 38, 40 and 42 are disposedin preferably equally spaced circumferential arrangement around theperiphery of exit orifice 32 and each lug extends radially inwardlytherefrom. The number, configuration and amount that the lugs extendinto the flow stream may be varied, but it has been found that a desiredproportion should be maintained in order to provide a balance betweenfluid dispersion and total range of the fluid stream. In the preferredpractice of the invention, it has been found that three lugs provide asymmetrical dispersion pattern; however, a greater number of lugs mayalso be found effective. It has been determined that a highly effectiveand satisfactory dispersion pattern can be achieved by sizing the lugsto extend radially inward by an amount of 0.026 inch (0.66 mm) from theinternal diameter of flow control diameter 36. This arrangement enablesthe exit orifice to be held constant over a wide range of flow controlelement sizes while varying the lug size. An exit orifice having aninternal diameter of 0.323 inch (8.20 mm) has been found particularlysuitable for flow rates of 2.0 through 10.0 gallons per minute. There isillustrated in FIG. 4 a chart showing the flow control orifice 36internal diameter measured in the relaxed state and the amount of inwardlug extension from exit orifice 32 for a given or desired flow rate ingallons per minute. A suitable lug width for the range of extensionsshown in FIG. 4 has been determined to be 0.060 inch (1.52 mm). Thus,from FIG. 4, for a desired flow rate the flow control internal orificediameter and lug extension may be determined and will be satisfactoryfor a 0.060 (1.52 mm) by width.

The relationship between lug extension and the area of the flow controlinternal diameter in the relaxed state may be expressed in terms of theratio expressed as a percent of the rib area projecting into the flowcontrol internal diameter to the area of the flow control internaldiameter. A range of 0.5% to 15.0% generally provides acceptabledispersion and a range of 0.6% to 8.0% provides optimal dispersion. Thefunctional effect of the lugs on the resultant fluid stream passingthrough the device will be subsequently described in greater detail.

Exit orifice 32 has a first diverging surface 44 immediately upstreamfrom lugs 38, 40 and 42, and a second diverging surface 46 locatedupstream from the first diverging surface. Surfaces 44 and 46 providesupport for the inner downstream face of the control member as itdeflects thereagainst under the forces transmitted by fluid flow.

A plurality of wrench flats in the form of preferably a square-pattern48 are formed on the downstream face of the outlet housing section andwhich provide engaging surfaces for a wrench or other attachment tool.

In operation, when the device is connected to a pressurized supply ofwater, the flow enters into inlet passageway 16 where it then encountersthe restrictive effects of control orifice 36. The resilient flowcontrol member 34 then axially deflects in a downstream direction anamount dependent upon the fluid pressure upstream therefrom with thedeflection varying the control orifice size. The change in controlorifice size enables the flow control member to compensate for changesin upstream pressure, thereby maintaining flow at a substantiallyconstant rate. As stated previously, the internal diameter of exitorifice 32 in sized greater than the diameter of the fluid streampassing therethrough to prevent needless reduction of the streamvelocity. Lugs 38, 40 and 42 are, however, sized to extend into thefluid stream a predetermined amount dependent upon the amount ofdispersion desired. The effect of the lugs is to form channels in thefluid stream causing partial deflection thereof whereupon the deflectedportion has a reduced velocity component, resulting in a uniformlydispersed fluid stream. In the preferred practice of the invention,greater control of the dispersion pattern is achieved by sizing the exitorifice diameter greater than the diameter of the fluid stream, therebyallowing only the lug members to deflect the stream flow. However, thedeflecting lugs are still effective even if the stream does, in fact,contact the periphery of the exit orifice whereupon the exit orificewill also influence the stream pattern.

There is illustrated in FIG. 3 the dispersion nozzle in an operativecondition showing the flow control member deflected in a downstreamdirection with first diverging section 46 supporting the flow controlmember against further axial deflection. The resultant fluid stream isillustrated generally by the arrows passing through exit orifice 32.

Referring now to FIGS. 5 and 6, an embodiment of the invention is shown,wherein the flow dispersion nozzle 10 is threadedly connected to asprinkler head shown schematically by reference numeral 50. A means forcontinuously rotating sprinkler head 50 about a vertical axis 51 isemployed and is represented schematically by reference numeral 52 andfunctions in response to water flowing therethrough. Rotating means 52may be of any type well known in the art, for example, thoseincorporating a turbine element mounted with associated drivingcomponents. A secondary supply conduit 54 is connected to rotating means52. Referring now particularly to FIG. 6, the remaining portions of theirrigation system are shown schematically and include a primary fluidconduit 56 fluidly connected to a pressurized source of irrigation water(not shown). Each secondary fluid conduit 54 is in turn connected toprimary fluid conduit 56. The horizontal spacing between adjacent supplyconduits and the vertical height of each conduit 54 are determined bythe range of the water stream exhausting from each sprinkler head 50.The details of the fluid connections between conduits are not shown,since details of this type form no part of the invention and are wellknown to those having ordinary skill in the art. In addition, the basicfluid flow path represented by FIG. 6 can be made part of a far moreextensive supply conduit grid without departing from the teachings ofthe invention.

Other embodiments and variations of this invention will occur to thoseskilled in the art and which are within the scope of the followingclaims.

I claim:
 1. A nozzle device for controlling the dispersion of apressurized supply of fluid, comprising:(a) housing means defining aninlet passage and a control chamber downstream from said inlet passageand further defining an outlet orifice located downstream from saidcontrol chamber and substantially aligned with said inlet passage in thedirection of flow; (b) flow control means disposed in said controlchamber, said flow control means having a control orifice therein forlimiting the fluid flow rate therethrough, said control orifice beingeffective for guiding said flow to an outwardly projecting fluid stream;(c) said outlet orifice having an internal transverse dimension greaterthan the periphery of said fluid stream such that said fluid stream issubstantially unobstructed while flowing therethrough; and (d) channelforming means for deflecting a portion of said fluid flow passingthrough said outlet orifice, said channel forming means being disposedaround the periphery of said outlet orifice and being effective forforming channels in and dispersing substantially uniformly said fluidstream downstream of said outlet orifice.
 2. A device as defined inclaim 1, wherein said channel forming means includes a plurality ofradially inwardly projecting lugs, said lugs being spacedcircumferentially about the inner periphery of said outlet orifice.
 3. Adevice as defined in claim 1, wherein said channel forming meansincludes a plurality of radially inwardly projecting lugs, said lugsbeing spaced circumferentially about the inner periphery of said outletorifice, with the ratio of the area of said lugs transverse to the flowdirection and projecting radially inwardly from said control orifice tothe area of said control orifice being in the range of 0.5% to 15.0%. 4.A device as defined in claim 1, wherein said channel forming meansincludes a plurality of radially inwardly projecting lugs, said lugsbeing spaced circumferentially about the inner periphery of said outletorifice, with the ratio of the area of said lugs transverse to the flowdirection and projecting radially inwardly from said control orifice tothe area of said control orifice being in the range of 0.6% to 8.0%. 5.A device as defined in claim 1, wherein said deflecting means arepositioned adjacent the downstream edge of said outlet orifice.
 6. Adevice as defined in claim 1, wherein said flow control means includes aresilient, disc-shaped member.
 7. A device as defined in claim 1,wherein the area transverse to the direction of flow of said outletorifice is at least 20% greater than the area of said control orifice asdetermined in a relaxed condition.
 8. An irrigation system for supplyingfluid from a pressurized source to an area to be irrigated,comprising:(a) primary fluid conduit means having an inlet adapted forconnection to said source; (b) at least one secondary conduit means eachhaving a fluid inlet and a fluid outlet, with the inlet of each of saidsecondary conduit means being in fluid communication with said primaryconduit means and operating for transferring said pressurized fluid fromsaid source to said secondary outlet; (c) sprinkler head means having afluid passageway therethrough with one of said sprinkler head meansbeing disposed in fluid communication with and rotatably connected tothe outlet of each of said secondary conduit means; (d) means forrotating each of said sprinkler head means in response to said fluidflowing through said sprinkler head means fluid passageway; (e) saidsprinkler head means including,(i) means defining a control chamberadjacent the sprinkler head means fluid outlet; (ii) means defining anoutlet orifice downstream from said control chamber at the sprinklerhead means fluid outlet; (f) flow control means disposed in said controlchamber, said flow control means having a control orifice therein forlimiting the fluid flow rate therethrough, said control orifice beingeffective for guiding said flow to an outwardly projecting fluid stream;and (g) said outlet orifice having an internal transverse dimensiongreater than the periphery of said fluid stream such that said fluidstream is substantially unobstructed while flowing therethrough; and (h)channel forming means for deflecting a portion of said fluid flowpassing through said outlet orifice, said channel forming means beingdisposed around the periphery of said outlet orifice, said channelforming means being effective for forming channels in and dispersingsubstantially uniformly said fluid stream downstream of said orifice. 9.A device as defined in claim 8, wherein said channel forming meansincludes a plurality of radially inwardly projecting lugs, said lugsbeing spaced circumferentially about the inner periphery of said outletorifice.
 10. A device as defined in claim 8, wherein said channelforming means includes a plurality of radially inwardly projecting lugs,said lugs being spaced circumferentially about the inner periphery ofsaid outlet orifice, with the ratio of the area of said lugs transverseto the flow direction and projecting radially inwardly from said controlorifice to the area of said control orifice being in the range of 0.5%to 15.0%.
 11. A device as defined in claim 8, wherein said channelforming means includes a plurality of radially inwardly projecting lugs,said lugs being spaced circumferentially about the inner periphery ofsaid outlet orifice, with the ratio of the area of said lugs transverseto the flow direction and projecting radially inwardly from said controlorifice to the area of said control orifice being in the range of 0.6%to 8.0%.
 12. A device as defined in claim 8, wherein said deflectingmeans are positioned adjacent the downstream edge of said outletorifice.
 13. A device as defined in claim 8, wherein said flow controlmeans includes a resilient, disc-shaped member.
 14. A device as definedin claim 8, wherein the area transverse to the direction of flow of saidoutlet orifice is at least 20% greater than the area of said controlorifice as determined in a relaxed condition.